Students with disabilities are almost twice as likely to be suspended from school as nondisabled students, with the highest rates among black children with disabilities.

According to a new analysis of Department of Education data, 13 percent of disabled students in kindergarten through 12th grade were suspended during the 2009-10 school year, compared with 7 percent of students without disabilities. Among black children with disabilities, which included those with learning difficulties, the rate was much higher: one out of every four was suspended at least once that school year.

The Center for Civil Rights Remedies at the University of California, Los Angeles, conducted the study of data from the Department of Education’s Office for Civil Rights, which originally released the raw statistics in March.

Policy makers and civil rights leaders worry about out-of-school suspensions because they often presage dropouts and can raise a child’s risk of future incarceration. Districts with high suspension rates also tend to be correlated with lower student achievement as measured by test scores.

The analysis, which reviewed data at the state and district levels, found that in 10 states, including California, Connecticut, Delaware and Illinois, more than a quarter of black students with disabilities were suspended in 2009-10. In Illinois, the rate was close to 42 percent, compared with about 8 percent for white students. New York and Florida were not included because of problems with their data.

“That’s a very disturbing pattern because kids with disabilities are supposed to be getting additional supports and counseling,” said Daniel J. Losen, senior education law and policy associate with the U.C.L.A. Civil Rights Project and an author of the report. “Kids with disabilities make up a very large proportion of the kids who are in the juvenile justice system, so it’s a very, very disturbing finding.”

In some districts, black male students with disabilities were suspended at a strikingly high rate. In Henrico County Public Schools in Virginia, for example, the report’s authors found that close to 92 percent of all black males with disabilities had been suspended one or more times during 2009-10, compared with just over 44 percent of white males with disabilities. In Memphis, a majority black district, nearly 53 percent of all black males with disabilities were suspended that year.

Black students in general were more likely to be suspended than any other racial group, although American Indians and Latinos were also suspended at much higher rates than whites. Among black students, one in six was suspended at least once in 2009-10, compared with one in 13 American Indians, one in 14 Latinos, and one in 20 whites.

Some districts suspend black students at well above the national average. The Pontiac School District in Michigan, for example, suspended 67.5 percent of its black students in 2009-10, and the East Jasper Consolidated School District in Heidelberg, Miss., suspended 63.5 percent of its black students.

Russlyn H. Ali, assistant secretary for civil rights in the Department of Education, said the office had opened 19 investigations in 15 states to examine districts where minority students were disproportionately disciplined. Ms. Ali said a complicated set of reasons was fueling the imbalances.

“In lots of these urban districts especially, the leadership and faculty are also people of color,” she said. “So it certainly doesn’t fit into the color-coded boxes of that ‘ism’ that we’ve used historically.”

Teachers struggle to deal with students who may be disruptive. “What most teachers complain about is that they have problem children and nobody helps them,” said Karen Lewis, president of the Chicago Teachers Union, citing ratio of students to social workers that was more than 1,000 to 1 in the district.

According to the Civil Rights Project analysis, Chicago schools suspended nearly 63 percent of their black students with disabilities in 2009-10.

This year, the Chicago Public Schools adopted plans to reduce suspensions and deal with behavioral issues up front. “I am a strong believer in limiting mandatory disciplinary actions that remove a child from their classroom and school, which in many cases ultimately causes more harm than good for those students,” Jean-Claude Brizard, chief executive of the Chicago Public Schools, said in a statement.

In Memphis, Patricia Toarmina, director of special education, said the district had received a grant to hire more social workers to help children with disabilities cope with situations that might cause them to misbehave.

Concerned by disparities in out-of-school suspensions in several districts in Florida, the Southern Poverty Law Center said on Tuesday that it had filed complaints with the Department of Education’s civil rights office against school districts in five counties, including Escambia, Okaloosa and Suwannee. The complaints say these districts imposed harsh disciplinary measures on black students at much higher rates than white students.

Stephanie Langer, staff attorney in the law center’s Florida office, said that in Escambia County, for example, black students accounted for 65 percent of all out-of-school suspensions, despite making up only 36 percent of the district population.

In some cases, Ms. Langer said, students were suspended for minor violations like taking a cellphone to class or violating a dress code.

Malcolm Thomas, superintendent of the Escambia schools, said the district had reduced the total number of suspensions by 43 percent since 2007-8. “What we have not done, and we can’t, is lower our expectations of good behavior for all students,” Mr. Thomas said.

Although administrators in the district may previously have suspended students for minor offenses, he said, they now focus on “serious breaches” like selling drugs or taking a gun to campus.

The authors of the Center for Civil Rights Remedies report found that although disparities were echoed across thousands of districts, some did not use suspension frequently.

Advocates for disabled students suggested that districts with high suspension rates might be able to learn from those that did not often resort to such measures.

“We want to take this report and say we know that viable alternatives exist,” said Diane Howard, staff attorney for juvenile justice and education for the National Disability Rights Network. “School districts and states both rich and poor are choosing not to suspend kids, so it’s not inevitable.”

This story, "Suspensions Are Higher for Disabled Students, Federal Data Indicate," originally appears at the New York Times News Service.